Track-type vehicles, such as crawler tractors, normally include a recoil system interconnecting the front track idler and track roller frame thereof. When a tractor is employed in operations wherein the undercarriage thereof is subjected to loads of high magnitude, such as a log skidding operation, the recoiling and return of a track idler to its initial, operational position must be effected in a closely controlled and efficient manner. In particular, it is desirable to reciprocate the track idler linearly without imposing any twisting or bending moments on the recoil system and undercarriage components associated therewith.
In the mechanical type recoil systems employing one or more return springs therein, the track idler is sometimes connected to the return spring by a yoke assembly and a slide bar reciprocally mounted in an annular bearing. Another type of mechanical recoil system includes a spring-biased tubular member having a track idler mounted forwardly therein. The tubular member is reciprocally mounted in a track roller frame.
Although slide bearings, per se, have been widely used in various applications wherein a pair of members necessarily reciprocate relative to each other, their use in recoil systems for track-type vehicles has been limited due to space, servicing, mounting problems and related difficulties. In the type of track-type vehicle or tractor under consideration, it is highly desirable to provide a compact recoil system that enables a workman to expeditiously assemble and disassemble the system for servicing purposes.
The present invention is directed to overcoming one or more of the problems as set forth above.